please some questions regarding electrical equipment protection in hazard areas:
1- We know for zener barrier we have exia for 2 faults by using 3 zener diodes and ib using 2 zener diodes. how we achieve ia and ib in galvanic isolator while we do not have the zener diodes construction?
2- How EXPx, Py and Pz different in panel/box construction to achieve their different zones allocation capability?
3- If we have transmitter with 2 Elec. protection mentioned in its label like EXi & EXd, is this mean this transmitter has these two protection capability? Or it means it has EXia in part of it (like termination compartment) and EXd in another part of it (like display and electronic card compartment)?
4- What tests should be done for EXe Boxes when get a new one?